Combined packaging machine

ABSTRACT

A combined packaging machine includes a device for paying out flat packaging material, a forming tube for deforming the flat packaging material into an endless tube, and a device for advancing the packaging material along the forming tube. A forming unit forms and welds respective longitudinal edges of consecutive pouches being produced, being capable of being moved in opposite directions longitudinally of the forming tube. A transverse welding unit operative for producing transverse seams between the successive ones of the pouches being produced is provided as well, as is a tucking-in unit that is provided on the transverse welding unit, being operative for tucking-in respective side regions of the successive pouches being produced. A control system selectively controls the operation of advancing, forming, transverse welding, and tucking-in units in coordination with one another in dependence on the type of pouch to be produced.

BACKGROUND OF THE INVENTION

1. Field of the Art

The present invention relates to the field of packaging and packaging machinery

2. State of the Art

Heretofore known continuous packaging machines are capable of producing flat pouches and filling them at a high rate of speed. The pouch is being formed from a flat packaging material that is converted on a forming element into an endless tube and subsequently transversely welded by welding jaws that conduct simultaneous movements along different trajectories, in most instances in the shape of the letter D. The principle of such a machine is disclosed in the U.S. Pat. No. 6,820,392 B2 or in the European patent document EP 0 469 819 B1. The apparatuses disclosed in these documents include two pairs of analogous welding jaws that are mounted on respective carriers that conduct movements, with the aid of carrying arms, along a circular path. The carrier arms are rotatably supported on main pivots that are coaxial, in each instance, for two opposing, non-conforming, welding jaws of the welding jaw pairs. Respective mechanisms for the positioning of the welding jaws, which ensure the corresponding relative positions of the welding surfaces during the rotation and the welding cycle, are mounted within these carrier arms. This apparatus includes just one, or two, driving units in dependence on the requirement for the change in the circumferential speed of the welding jaws in the course of a single revolution.

A second known principle of the production of pouches is, in its first phase, similar to that described above, where an endless tube is formed on a forming element. However, the transverse welding and separation of the pouches is performed by a pair of opposing welding jaws that move in directions concurrent with and opposite to the direction of advancement of the packaging material, respectively. The closing of the welding jaws, and thus the welding and separation of the packaging material, takes place during the concurrent movement phase. A further possibility in this system is the supplementation of these welding jaws with equipment for the insetting of the sides of the pouches, so that it is possible, in the course of the operation of the machine employing this principle, to produce a pouch with a folded bottom. A Machine using this principle is disclosed in the European patent document EP 0 255 474 B1 and in the U.S. Pat. No. 4,757,668. The equipment disclosed in these publications is constituted by a single unit for transverse welding that is movable in the vertical directions. The principle of this equipment renders possible to produce flat pouches during the continuous advancement of the endless tube of the packaging material.

A third known principle of the production of pouches once more begins as the two described above in that an endless tube is formed from the packaging material on a forming element The transverse welding and separation of the packaging material is performed in each instance by one of several pairs of welding jaws that move along oval tracks. These tracks are supported in the machine in such a manner that the welding jaws that move along them contact the packaging material with their active surfaces during a certain phase of their movement and simultaneously clamp the packaging material between these surfaces so that they weld the material. The speed of movement of the material and of the welding jaws is identical during this phase and is controlled by the control system of the machine. The principle of such a machine is disclosed in the German patent application DE 103 47 013 A1.

A fourth known principle of the production of the pouches is similar to the third one. However, the packaging material is shaped in a different manner, without a forming element, by simply by folding a flat foil over. This foil is subsequently longitudinally welded and filled. The transverse welding jaws in this case once more move along oval tracks, but their active surface do not maintain a concurrent position during their movement along the oval but rather rotate, so that they undergo a turning though 360° in the course of one cycle. The principle of such a machine is disclosed in the patent application WO 00/64753. The equipment employing this principle renders it possible to produce flat pouches during a continuous advancement of the endless tube of packaging material.

The formation of a pouch with welded edges using welding jaws arranged symmetrically around the periphery of the forming tube was heretofore possible only when the packaging machine operates in an intermittent regime in that closing of all welding jaws must occur. As a result of this, the advancement of the packaging foil has to be stopped for the time period needed for the welding of the foil at the edges of the pouch. The principle of such equipment is disclosed in the European patent application EP 1 609 720 A1.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a packaging machine capable of operating in a continuous operating mode.

It is another object of the present invention so to construct the packaging machine of the present invention as to be able to operate in an intermittent operating mode as well.

Still another object of the present invention is to design the packaging machine in such a manner as to be very compact and yet include all equipment needed for producing pouches of several different types by selective activation of its various units in dependence on the desired characteristics of the pouches to be produced during a given production run.

In pursuance of these objects and others that will become apparent hereafter, the present invention relates to a combined packaging machine that comprises means for paying out flat packaging material; a forming tube for deforming the flat packaging material into an endless tube; means for advancing the packaging material along the forming tube; means for forming and welding respective longitudinal edges of consecutive pouches being produced, means for moving said forming means in opposite directions longitudinally of said forming tube, means for producing transverse seams between the successive ones of the pouches being produced; means provided on said producing means for tucking-in respective side regions of the successive pouches being produced; and means for selectively controlling the operation of said advancing, forming, producing and tucking-in means in coordination with one another in dependence on the type of pouches to be produced.

Because of its construction, the combined packaging machine according to the present invention is thus capable of producing several different types of pouches in different runs, on one and the same packaging machine, with minimum requirements for alteration of the machine. The concept of the resent invention involves the provision of several operational units that can be selectively activated by a control system to cooperate with one another in the production of several different types of pouches.

BRIEF DESCRIPTION OF THE DRAWING

The sole FIGURE of the drawing is a simplified front elevational view of an example of a combined packaging machine embodying the present invention.

DETAILED DESCRIPTION OF THE CURRENTLY PREFERRED EMBODIMENT

Referring now to the single FIGURE of the drawing in detail, it is to be mentioned first that the packaging machine embodying the present invention includes many individual components and/or devices that are well known to and routinely employed by those versed in the field of packaging machinery, so that they need not and hence will not be disclosed here in any detail. Moreover, in order to simplify the illustration of the packaging machine constructed in accordance with the present invention, just one view thereof, which is defined here as being a front view even though in the actual machine it may constitute a side or a rear view, is presented here; however, it is to be understood that, whenever a reference is being made to more than one component of the same kind, not all of them will necessarily be visible in the drawing inasmuch as some of them will be hidden behind their identical counterparts that are situated in front of them as considered in such front view, This obscuration will not be specifically mentioned in the following description. It is further to be mentioned that, while the disclosure consistently refers to the products of the packaging machine as pouches, they may also to be considered to be closed bags, packs, sacks or the like. Yet further, it is to be understood that such pouches are, as customary, filled with some contents prior to their closure by a transverse weld.

As alluded to before, the combined packaging machine in accordance with the implementation that is depicted in the drawing is equipped with standard building blocks mounted on a frame 1 of the packaging machine, such as support for a supply 4 of packaging material 3, guiding units 5 and 6 each of which contains several guiding rollers over which the packaging material 3 being withdrawn from the supply 4 is guided in a known manner and which may also include respective devices for connecting the packaging materials 3 of consecutive supplies 4 and/or devices for marking the packaging material 3, and a forming tube 2 on which the originally flat packaging material 3 advancing from the guiding unit 6 is deformed into an endless packaging material tube, and an advancing device 7 with its drive 8 that acts on the packaging material 3 at the region of the forming tube 2 to advance such packaging material 3. However, in addition to such standard building blocks or units, the machine in accordance with the present invention includes further operational units 10 and 20 that differ from heretofore proposed solutions.

A first one of such further operational units that differ from those proposed before is a device 10 for the production and welding of the longitudinal edges of the pouch being formed. This device 10 is accommodated within the packaging machine frame 1 around the forming tube 2 of the packaging machine that deforms the originally flat packaging material 3 into the endless tube. Main components of this device 10 include, in the illustrated implementation, four vertical welding jaws 13 that are symmetrically distributed around the periphery of the forming tube 2. These welding jaws 13 are mounted on a common platform 14 that has a frame-shaped configuration at least at the region of the forming tube 2 to embrace the same with predetermined clearance therefrom, The welding jaws 13 are mounted on the platform 14 in such a manner that their active surfaces are oriented parallel to the axis of the forming tube 2, and that their positions can be adjusted in directions normal to this axis to take the diameter of the forming tube and hence the transverse dimensions of the packaging material tube formed thereon into consideration. The platform 14 is connected to a main carrier 15 that, in turn, is supported on one or more guiding members 16. The respective guiding member 16 is supported on an elongated guide element 9 extending parallel to the axis of the forming tube 2 for sliding along the same. The respective guide element 9, or each of them, is secured to the machine frame 1 and enables movement of the entire longitudinal welding device 10 with respect to the machine frame 1 in opposite directions along the longitudinal axis of the forming tube 2. The closing and opening movements of all four vertical welding jaws 13 is accomplished by a drive 17 that is mounted on the common platform 14 for the vertical welding jaws 13. The movement of the entire platform 14 with all the components mounted thereon is achieved by a servomotor 18 via a link chain transmission, a toothed rack-and-pinion transmission or an advancing screw transmission, either one being of a conventional construction. The speed of rotation of the driving servomotor 18 is controlled in dependence on the chosen speed of the packaging machine, by a central control system 40. The speed of movement of the longitudinal welding device 10 is identical during the performance of the longitudinal welding operation with that of the advancement of the tubular packaging material 3 as determined by the advancing device 7. This speed is higher than that during the return movement of the longitudinal welding device 10 to its initial position and is chosen in such a manner as to assure the longitudinal welding of the packaging material 3 without any gaps between consecutive longitudinal welded joints.

A second one of such further operational units that differ from those proposed before is a device 20 for the welding of the transverse edges of the pouch being formed. This device 20 is accommodated within the packaging machine frame 1 in the space below the forming tube. Main components of this device 20 include, in the illustrated implementation, two transverse welding jaws 23 that are symmetrically situated to the opposite sides with respect to the plane of the transverse weld that includes the longitudinal axis of the forming tube 2 and is perpendicular to the plane of the drawing. The transverse welding jaws 23 are mounted on a common platform 24 in such a manner that their active surfaces are parallel with this transverse welding plane that includes the longitudinal axis of the forming tube 2 while each of them as a whole extends along this welding plane but transversely to the advancement direction of the tubular packaging material or, more particularly, the pouch being formed therefrom. A drive 27 for opening and closing these transverse jaws 23 is mounted on the platform 24 as well. The common platform 24 has a frame-shaped configuration at least at the region surrounding the advancement path of the tubular packaging material 3 to embrace such path with a predetermined clearance therefrom. The platform 24 is connected to a main carrier 25 that, in turn, is supported on one or more guiding members 26. The respective guiding member 26 is slidably supported on the aforementioned elongated guide element 9 that is secured to the machine frame 1 and enables movement of the entire longitudinal welding device 20 with respect to the machine frame 1 in opposite directions along the longitudinal axis of the forming tube 2. The movement of the entire platform 24 with all the components mounted thereon is achieved by a servomotor 28 via another link chain transmission, a toothed rack-and-pinion transmission or an advancing screw transmission, either one being of a conventional construction. The speed of rotation of the driving servomotor 28 is controlled by the central control system 40 in dependence on the chosen speed of the packaging machine as well. The speed of movement of the longitudinal welding device 20 is once more identical during the performance of the longitudinal welding operation with that of the advancement of the tubular packaging material 3 as determined by the advancing device 7. This speed is higher than that during the return movement of the transverse welding device 20 to its initial position and is chosen in such a manner as to assure the transverse welding of the packaging material 3 at locations corresponding to the desired length of the pouch.

This second operational unit 20 of non-conventional construction is supplemented by a device 30 for the transverse tucking-in of the sides of the pouches. The device for the transverse tucking-in of the sides of the pouches is mounted on the common platform 24 for the transverse welding jaws 23 and includes pairs of tucking-in members 31 and 32. These pairs are situated symmetrically to the opposite sides of the common frame 24 at locations through which the aforementioned welding plane defined by the closed active surfaces of the transverse welding jaws 23, i.e. above and underneath the platform 24. Their individual tucking-in members 31 and 32 are situated in front of and behind the plane of the drawing, respectively, and they are movable to a limited extent toward and away from each other. This movement of the individual tucking-in members 31 and 32 is caused in dependence on the desired shape of the pouch and on the instantaneous position and/or movement of the platform 24, in a manner determined by the control system 40, by a non-illustrated drive or a conventional construction that is also carried by the common platform 24. On a packaging machine equipped with this tucking-in device 30, it is possible to produce pouches with tucked-in sides and folded bottoms, where the pairs of tucking-in members 32 tuck in the sides of the preceding pouch at its upper regions of their sides as considered in the drawing, whereas the pairs of the tucking-in members 31 tuck-in the sides of the next-following pouch at the lower regions of its sides and of the bottom of the pouch.

It is possible to produce several different types of pouches on the packaging machine of the just-described construction, by the operating personnel choosing the appropriate program in the control system 40 of the packaging machine.

A basic pouch type is a cushion-shaped pouch. During the operation of the packaging machine to produce such pouches, the advancing device 7 for advancing the packaging material 3 with its drive 8, as well as the transverse welding jaws 23, are active. The servomotor 28 moves the platform 24 carrying the transverse welding jaws 23 to its upper end position from where these jaws 23 move, together with their platform 24, downwardly at the same speed as the tubular packaging material 3 moves under the action of the then active advancing device 7. The drive 27 closes the transverse welding jaws 23 and opens them again just ahead of the termination of the downward movement of the platform 24. When the packaging machine is being operated in an intermittent operational regime, the platform 24 remains in its upper end position, the advancing device 7 advances the packaging material 3 while the transverse jaws 23 are open in the downward direction by the desired length of the pouch and then ceases to perform its advancing activity, whereupon the transverse welding jaw drive 27 closes the transverse jaws 23 to perform the transverse welding operation. Then the drive 27 opens the welding jaws 23 and the whole process can be repeated for the production of the next-following pouch.

Another pouch type that the machine in accordance with the present invention is capable of producing is a pouch with tucked-in sides and a folded bottom. The advancing device 7 for advancing the packaging material 3 with its drive 8, as well as the transverse welding jaws 23, are active during the operation of the packaging machine in this operating regime. The servomotor 28 moves the platform 24 carrying the transverse welding jaws 23 to its upper end position from where these jaws 23 move, together with their platform 24, downwardly at the same speed as the tubular packaging material 3 advances under the action of the then active advancing device 7. The drive 27 closes the transverse welding jaws 23; simultaneously with such closing, the device 30 for the tucking-in of the sides of the pouches is activated. The drive 27 opens the transverse jaws 23 again just ahead of the termination of the downward movement of the platform 24, and the device 30 for the tucking-in of the sides of the pouches is returned into its original position at the same time. When the packaging machine is being operated in an intermittent operational regime, the platform 24 remains in its upper end position, the advancing device 7 advances the packaging material 3 while the transverse jaws 23 are open in the downward direction by the desired length of the pouch and then ceases to perform its advancing activity, whereupon the drive 27 closes the transverse jaws 23 to perform the transverse welding operation. The device 30 for the tucking-in of the sides of the pouches is put into operation during the time that the transverse welding jaws 23 are being closed. After the welding operation is concluded, the transverse welding jaws 23 are opened and the device 30 for the tucking-in of the sides of the pouches is returned into its initial position.

The last type of pouch to be mentioned here that can be produced on the packaging machine of the present invention is a pouch with welded lateral edges and with tucked-in sides and a folded bottom. The advancing device 7 for advancing the packaging material 3 with its drive 8, as well as the longitudinal welding jaws 13 and the transverse welding jaws 23, are active during the operation of the packaging machine in this operating regime. The servomotor 18 moves the platform 14 carrying the longitudinal welding jaws 13 to its upper end position, while the servomotor 28 moves the platform 24 carrying the transverse welding jaws 23 to its upper end position in synchronism with the platform 14 carrying the longitudinal welding jaws 13. From these upper end positions these jaws 13 and 23 move, together with their respective platforms 14 and 24, in a synchronous manner downwardly at the same speed as the tubular packaging material 3 advances under the action of the then active advancing device 7. The drives 17 and 27 close all of their associated longitudinal and transverse welding jaws 13 and 23; simultaneously with such closing, the device 30 for the tucking-in of the sides of the pouches is activated. The drives 17 and 27 open the associated longitudinal and transverse jaws 13 and 23 again just ahead of the termination of the downward movement of the platforms 14 and 24, and the device 30 for the tucking-in of the sides of the pouches is returned into its original position at the same time. In the event that the packaging machine is being operated in an intermittent operational regime, the platform 14 with the longitudinal welding jaws 13 and the platform 24 with the transverse welding jaws 13 remain in their respective upper end positions, the advancing device 7 advances the packaging material 3 while both the longitudinal and the transverse jaws 13 and 23 are open in the downward direction by the desired length of the pouch and then ceases to perform its advancing activity, whereupon the drives 17 and 27 close the respective associated longitudinal and transverse welding jaws 13 and 23 to perform the longitudinal and transverse welding operations. The device 30 for the tucking-in of the sides of the pouches is put into operation during the time that the transverse welding jaws 23 are being closed. After the welding operation is concluded, all the longitudinal and transverse welding jaws 13 and 23 are opened by their associated drives 17 and 27 and the device 30 for the tucking-in of the sides of the pouches is returned into its initial position.

Without further analysis, the foregoing will so fully reveal the present invention that others can, by applying ordinary skill in the art, readily implement the same without having resort to undue experimentation.

While the present invention has been described and illustrated as employed to produce several different types of pouches, it is not intended to be limited to the details shown since various modifications and changes can easily be made without departing from the spirit and scope of the present invention. 

1. A combined packaging machine comprising means for paying out flat packaging material; a forming tube for deforming the flat packaging material into an endless tube; means for advancing the packaging material along the forming tube; means for forming and welding respective longitudinal edges of consecutive pouches being produced, means for moving said forming means in opposite directions longitudinally of said forming tube, means for producing transverse seams between the successive ones of the pouches being produced; means provided on said producing means for tucking-in respective side regions of the successive pouches being produced; and means for selectively controlling the operation of said advancing, forming, producing and tucking-in means in coordination with one another in dependence on the type of pouch to be produced. 